1. Field of the Invention
This invention relates to purification of air and, more specifically, to creating a positive pressure environment with purified air.
2. Related Art
There are two main types of room air purifiers today. One type works well with all forms of forced air heating and or cooling systems commonly found in roughly 80% of the homes in the United States (US Census).
The other type works in an atypical, controlled room environment. More specifically, a room without open doors, open windows, drafts and or forced air supply ducts. The following information supports this position.
According to the U.S. EPA “portable room air cleaners generally contain a fan to circulate the air and use one or more of the air-cleaning technologies discussed above. They may be an option if a home is not equipped with a furnace or a central air-conditioning system.” This information was recently published in the EPA's Residential Air Cleaning Devices publication.
Furthermore, The AHAM (Association of Home Appliance Manufactures) CADR (Clean Air Delivery Rate) long accepted standard for Evaluating the performance of portable air cleaners, is overdue in recognizing the specificity in the EPA's new position. AHAM does indicate, in the CADR certificate, “Portable air cleaners will be much more effective in rooms where all doors and windows are closed.” Unlike the EPA's new revelation, AHAM continues to fall short and does not recognize, what is, perhaps, the largest source of contaminated air entering a room, the supply duct of “a furnace or a central air-conditioning system” (EPA).
AHAM and the EPA worked together decades ago to create the CADR testing and certification program and have updated the testing protocol as recently as 2006 and 2008.
Indoor air quality ranks among the top 5 environmental risks to humans in the United States. The costs are measured in tens of millions of people suffering from allergies and asthma and more formidable airborne VOCs, gases, and other contaminants. The cost to the United States is tens of billions of dollars in health care and lost productivity at work. There are too many losses to cover here in detail. The EPA has an exhaustive list of the consequences of poor indoor air quality.
Distinct from the existing two classes of air purifies, the air purifier disclosed in US Patent Application Publication No. 20090023376 represents a new class of room air purifier that effectively manages contaminated air from a forced air system and also manages air from the room. This device can also manage room air temperature by adding the proper amount of heating air or cooling air to a room utilizing only one supply duct.
Because most rooms have several supply ducts, uncontrolled ducts in the room should be closed. The air purifier unit will install and connect to (seal to) one supply duct and the expense of additional room air purifier units for a single room is typically not necessary.
This new air purifier will also manage air from any source outside of the room it can be connected to, and will also manage the ambient room air as well.
By design, the air purifier is capable of drawing a necessary amount of air continuously from any source outside of the room. Any in-room return air duct can be blocked or partially blocked, and the room will overflow with the additional air, and this excess air can flow out of a doorway, for example, thereby preventing untreated hallway air from entering the room through the open doorway. Drafts in the hallway are kept at bay and not allowed to circulate freely into the treated room.
The air purifier described is represented in the cut-away side view drawing in FIG. 1.